Latching system



April 23, 1968 G. T. BAGGOTT LATCHING SYSTEM Filed July 29, 1966 S RW M,p 05,/ MMS w S# mf @i m ffii/f 5 v.. B

April 23, 1968 G. T. BAGGOTT LATCHING SYSTEM 2 Sheets-Sheet Filed July29, 1966 @lilo i-Filed July 29, 1966, Ser. No. 568,847 lli Claims. (Cl.S12-411) The present invention relates generally to latching systems,and more specifically to a system of locking one portable storage unitatop another.

ln the art of materials handling, various storage units or cabinets havebeen developed for different purposes. All too frequently, patterns ofconsumption require movement of particular material to particularlocations in amounts not predictable at the time of storage. As aresult, effort is expended in the time-consuming task of breaking downand repacking the stored material. Mobile vehicles are an obviousresponse to this problem. Almost inevitably, however, mobility resultsin an uneconomical use ot oor space, especially where the materialinvolved is weighty' or bulky.

An additional problem is presented when some sort of control must beexerted on the environment of the material, such as temperature orpressure. In such cases, it may be impracticable to maintain such`control throughout the loading or unloading of a large storage unit.

Accordingly, the main object of this invention is to provide a system oflatching storage units which permits mobility, effective use of floorspace, and maintenance of separate environmental controls on separateunits.

Another object is to provide a system for securely locking one storageunit atop another.

Still another object is to provide a system for material handling whichavoids the necessity of repeated unloading or repacking.

Other important objects and advantages of my invention will be apparentto those skilled in the art from the following description of apreferred embodiment of it taken together with the accompanying drawingsin which:

.FGURE l shows in perspective two typical storage units includingpositioning and latching means holding the units in a stacked and lockedrelationship;

FIGURE 2 is a side elevation view in enlarged scale of the latchingmeans and positions of the two stacked storage units shown in FIGURE l;

FGURE 3 is an end elevation view showing portions ot two stacked storageunits and parts of the latching mechanism; and

BiC-URE 4 is an enlarged view ot the resilientlybiased connectionassembly shown at the right of FlG- URE 2 with portions omitted forclarity.

A latching system typical of my invention is shown in lidURE 1 inconnection and in combination with two stacked storage units l). Storageunits 10 are of a convenient size and type commonly used in the foodhandling equipn'ient and other industries. These box-like units areoften insulated and contain either refrigeration or heating apparatus tomaintain the contents at a desired temperature. Units 10 are loadable orunloadable through doors ll and are provided with casters 12 for easymovement and maximum mobility. In the past, storage units of the generaltype shown have been used individually, each standing and moving on itsown set of casters 12 and each occupying valuable space on the StatesPatent O ICC floor. The latching system of my invention now permits suchstorage units, both with and without casters, to be easily,conveniently, and safely stacked and used, moved, and transported in astacked relationship as well as to be unstacked and employedindividually as may be most convenient at the time.

As shown in FIGURE l, the latching system comprises tour latchingassemblies i3. Each latching assembly 13 comprises a latch arm 14 and alatch arm storing bracket l5 mounted on one of the units to be latched,and a cooperating latch strike 16, mounted on the other of the units tobe latched. The apparatus, as described and drawn, illustrates a form ofthe invention with the latch arm l and latch arm storing bracket 15attached to the lower storage unit, and cooperating latch Strike 16attached to the upper storage unit, though the reverse configurationwould work as well. Unitormity in this respect among the storage unitsin use in a given arca is, of course, desirable.

The latch ram le of each latching assembly 13 is adapted to be extendedfrom the unit carrying them towart and into a position and condition oflatching engagement with the cooperating latch strike 16 of theassembly. When all the assemblies 13 comprising the system are latched,the two storage units are positively aligned and secured againstrelative movement. When the storage :units are to be separated, thelatch arms and strikes disengaged and the latch arms retracted into astoring position of engagement with their respective storing brackets15'.

The latching assemblies 13 making up the system are all the same inconstruction and operation and, therefore, only one will be described indetail. lEach latch arm 14 is pivotally connected at one end by shoulderscrew 17 to a side of the lower storage unit 1l), preferably adiacentthe top surface. The plurality of latch arms 14 comprising the systemare preferably horizontally spaced apart around the top surface andalong the unit sides to best secure the two units together and againstrelative movement between them.

Latch arm 14 is pivoted for swinging movement generally in the plane ofthe side to which it is attached and containing the latch strike 1.6 itis to engage, It swings between its associated latch arm storing bracketl5 and latch strike 16. Swinging movement through a greater arc isprevented by stop pins 18 and i9 xedly mounted on the side of a storageunit 1d. Stop pins 1S and 1 9 each serve to prevent latch arm 15 fromswinging in one direction beyond its stored and latching positions,respectively. As explained more fully below, two or more latch armsltand their associated stop pins l@ cooperate to vertically align and topositively position two storage units l() which they latch together.

The longitudinal edges of latch arms 14 preferably coinpriseoutwardly-turned flanges 2t), particularly shown in FIGURE 3, whichcontribute stillness to the arms and partially shield the moving partsof connection assembly 19 described below. Flanges 2o also provideadequate surfaces for bearing engagement with stop pins 1S when thelatch arm is in stored position, and stop pins 19 when the latch arm isin its lat-ching position.

When extended for latching, latch arm 1d substantially reaches itsassociated latch strike 16 on the other storage unit. Aresiliently-biased connection assembly 21 is mounted on the free,swinging end of each latch arm 14.

3 As viewed particularly in FGURE 4, a toggle lever 22 is mounted forswinging movement at the end of latch arm 14. Toggle lever 22 swingsabout hinge pin 23 carried in outwardly extending ears 24cm the end oflatch arm 14.

Toggle lever 22 is also provided with a swinging bail 25 mounted forswinging movement about the axis of pin 26 carried in latch arm 14spaced from the parallel to hinge pin 23. Swinging bail 25 preferablyconsists of a pair of resiliently yieldable side links connectedtogether at one end by latch pin 27 and at the other end by pin 26. Theyieldable resilience of the side links is preferably provided by meansof two bar elements 28 and 29 extending longitudinally beside each otherand passing through the center of a coil spring 30. One end 31 of eachof elements 2S and 29 is turned outwardly to bear against an end ofspring 30 so that any etort to lengthen the link by moving elements 23and 29 apart is resiliently resisted by spring 30 acting in compression.

Toggle lever 22 terminates in a lifting tab 32 for convenient and easyoperation. It will be seen that connection assembly 21 operatesgenerally in the well-known manner of an overcenter toggle latch,enhanced, however, by the addition of the resiiiently yieldable sidelinks described above. Operation of toggle lever 22 effectively changesthe distance between latch pin 27 and pivot point 17 by twice the amountof the distance between hinge pin 23 and pin 26, plus anything realizedby compression of springs 30 and consequent extension of the side linksof bail 2S. The dimensions involved should require some compression ofspring 30 when latching assemblies 13, including connection assemblies21, are latched and engaged with latch strikes 16.

Latch strikes 16 are attached by suitable means, such as rivets 33, tothe side of each storage unit at spaced apart points corresponding toand for cooperation with spaced apart latch arms 14. Each latch strike16 is provided with an outwardly-extending hook portion 34, see FIGURE3, adapted to receive latch pin 27 of a resiliently-biased connectionassembly 21. Latch strikes 16 are preferably located on one storage unit10 directly above pivot point 17 loc-ations of latch arms 14 on theother storage unit 10, though they may be located out of verticalalignment, it being desirable, however, that the latch arms act to pullthe latched storage units together to a substantial extent.

Latch arm storing brackets -are attached on the side of the storage unit10 by suitable fastening means such as rivets 35. Latch arm storingbracket 15 has outwardlyextending hooked portions 36 at either endadapted to receive latch pins 27 of resiliently-biased connectionassemblies 21 of the adjacent latch arms 14 when the latch arms are instored position.

As shown, the invention is useful in connection with storage unitsequipped with casters. With this invention, such. castered units wouldbe most dilhcult, if not impossible, to use and move about in a stackedrelationship. The casters 12 may be made of any suitable material. Ifrubber or resilient casters are used, for example, it is desirable thatthey be compressed when the storage units are latched together. Thetension thus achieved in the latching assemblies 13, when added to thatof their own springs 30, will aid in maintaining the units 10 in asecure stacked relationship.

Each storage unit is preferably provided. with tracks 37 for aiding instacking and unstacking the units by receiving and guiding casters 12.Additionally, the tracks serve to align the units and to help maintainthem in a secure stacked relationship.

To secure two storage units 10 together, one is positioned atop theother with the casters 12 of the upper one on the tracks 37 of the lowerone and wtih the latch strikes 16 on the upper unit suitably aligned forengagement by the latch arm 14 on the lower unit. Latch arms 14 arereleased from their stored position of connection from swinging pastthat position by stop pin 19. Tab Y 32 of toggle lever 22 is againlifted so that latch pin 27 reaches over the hook portion 34 on latchstrike 16. Tab 32 is then pushed down, drawing latch pin 27 intolatching engagement with latch strike 16 and compressing springs 30. Thecompression of springs 30 resliently biases each latched connectionbetween the storage units and, thus, resiliently draws them together.

When casters 12 are constructed, in whole or in part, of rubber or otherresilient material, the latching system preferably operates to compresscasters 12 when the units are latched together, resulting in additionalresilientlybiased reaction tending to hold the latched units togetherand against relative movement.

When the plurality of latching assemblies 13 are thus latched, storageunits 10, stacked one atop the other, should be capable of substantiallyall the mobility of a single unit 10, while capacity and utility aregreatly increased.

VlVly invention envisions the possibility of utilizing different shapesof units, and possibly the stacking of more than two at once, as well asother variations on the preferred form. For this reason, l do not wishto be limited to the particular form described above.

I claim:

1. In combination,

a pair of separate movable cabinets adapted for stacking one atop theother, and a plurality of laterally spaced latching means forpositioning and releasably latching the cabinets in a stackedrelations-hip and for limiting relative movement therebetween, each ofsaid latching means comprising a latch strike attached to one of saidcabinets,

a latch arm storing bracket attached to the other of said cabinets,

a latch arm associated with said latch strike and pivotally connected tothe other of said cabinets and swingable toward and away from said latchstrike and said latch arm storing bracket when said cabinets arestacked, and

resilient tension means mounted on said latch arm for releasablyconnecting said latch arm to said latch strike in a resiliently-biasedconnection urging said latch strike toward the point of pivotalconnection of said latch arm when directed toward said latch strike 'andrestraining said separate movable cabinets against relative movement intheir stacked relationship and for releasably connecting to said latcharm storing bracket for storing.

2. The combination of claim 1 in which each separate cabinet is equippedwith a plurality of said latch strikes,

said latch arm storing brackets, said latch arms, and said resilienttension means.

3. The combination of claim 2 in which each separate cabinet is mountedon casters, and is provided with means for guiding the casters of anassociated cabinet such that said cabinets are maintained in verticalalignment.

4. The combination of claim 3 in which each of said latch means isprovided with means to prevent rotation of said latch arm beyond itslocked and rest positions.

5. The combination 0f claim 4 in which said casters are compressed whensaid cabinets are stacked.

6. The combination of claim 2 in which each of said latch means isprovided with means to prevent rotation of said latch arm beyond itslocked and rest positions.

7. The combination of claim 3 in which said casters are compressed whensaid cabinets are stacked.

cabinet is mounted on casters, and is provided with means ,d S2 forguiding the casters of an associated cabinet such that 2,018,191 saidcabinets are maintained in vertical alignment. 2,267,403 9. Thecombination of claim 8 in which said casters are 2,556,113 compressedwhen said cabinets are stacked.

1). The combination of `claim 9 in which each of said 5 latch means isprovided with means to prevent rotation of 441,443 said latch farmbeyond its locked and rest positions. 526,817 763,490

References Cited UNITED STATES PATENTS 10/ 1935 Schmidt 292-246 12/1941Herold 16-45 6/1951 Shaw et al. 292-246 FOREIGN PATENTS 3/ 1927 Germany.11/ 1929 Germany. 12/1956 Great Britain.

10 BGBBY R. GAY, Primary Examiner.

JAMES L. KOHNEN, Assistant Examiner.

1. IN COMBINATION, A PAIR OF SEPARATE MOVABLE CABINETS ADAPTED FORSTACKING ONE ATOP THE OTHER, AND A PLURALITY OF LATERALLY SPACEDLATCHING MEANS FOR POSITIONING AND RELEASABLY LATCHING THE CABINETS IN ASTACKED RELATIONSHIP AND FOR LIMITING RELATIVE MOVEMENT THEREBETWEEN,EACH OF SAID LATCHING MEANS COMPRISING A LATCH STRIKE ATTACHED TO ONE OFSAID CABINETS, A LATCH ARM STORING BRACKET ATTACHED TO THE OTHER OF SAIDCABINETS, A LATCH ARM ASSOCIATED WITH SAID LATCH STRIKE AND PIVOTALLYCONNECTED TO THE OTHER OF SAID CABINETS AND SWINGABLE TOWARD AND AWAYFROM SAID LATCH STRIKE AND SAID LATCH ARM STORING BRACKET WHEN SAIDCABINETS ARE STACKED, AND RESILIENT TENSION MEANS MOUNTED ON SAID LATCHARM FOR RELEASABLY CONNECTING SAID LATCH ARM TO SAID LATCH STRIKE IN ARESILIENTLY-BIASED CONNECTION URGING SAID LATCH STRIKE TOWARD THE POINTOF PIVOTAL CONNECTION OF SAID LATCH ARM WHEN DIRECTED TOWARD SAID LATCHSTRIKE AND RESTRAINING SAID SEPARATE MOVABLE CABINETS AGAINST RELATIVEMOVEMENT IN THEIR STACKED RELATIONSHIP AND FOR RELEASABLY CONNECTING TOSAID LATCH ARM STORING BRACKET FOR STORING.